1. Field of the Invention
This invention relates to blade sharpeners of the straight or serrated blade type and more particularly to a novel blade sharpener which will effectively sharpen the edge of knives, scissors or the like and which will not carry into the blade to be sharpened, any impurities or abrasion marks carried on the sharpening element.
2. Brief Description of the Prior Art
In the past, it has been the conventional practice the sharpen blades by drawing the cutting edge of the blade over an abrasive material. One such prior device is shown and disclosed in U.S. Pat. No. 3,894,362. Although this device is useful in the sharpening of serrated blades in particular, difficulties have been encountered when attempting to use the device for sharpening a straight edge or when attempting to sharpen the blades associated with scissors. These problems and difficulties stem largely from the fact that the sharpening elements in the aforementioned patent provide a rounded surface to the blade and this has a tendency to draw metal from the blade so that it will clog or load up the pores of the abrasive material on the sharpening element. It is clear from a reading of the prior patent that the element is a rod and is intended to include a circular surface as a sharpening medium. Such a cylindrical rod may work well with serrated edges as shown in FIG. 3 of the prior patent; however, a straight edge blade does not sharpen well on a cylindrical surface. In order for the prior device to be used, it is necessary that the person sharpening the blade constantly rotates or turns the cylindrical rod in its receiving hole so as to offer a clean surface to the blade during the sharpening procedure. Such a procedure is awkward and cumbersome which requires added steps that are normally to be avoided since the sharpening of a knife is a dangerous procedure.
Therefore, a long standing need has existed to provide a novel knife sharpener which will also sharpen the edges of scissors, chisels and other cutting implements and which will avoid the problem of premature clogging or loading due to the gathering of removed material from the cutting edge as it is sharpened.